A fluid composition for use in inflatable bag plugging of an earth bore hole

ABSTRACT

A fluid composition for inflating a bag or bladder used in plugging earth drill or bore holes. The fluid composition comprises: a hydrocarbon gas or hydrocarbon gas blend; a carrier; and an emulsifier. In preferred embodiments the hydrocarbon gas comprises butane or propane; the carrier comprises water; and the emulsifier comprises a carbomer, such as a cross-linked polyacrylic polymer, and/or coconut diethanolamide. An aerosol dispenser may supply the fluid composition as foam to the bag.

FIELD OF THE INVENTION

The present invention relates to a fluid composition. In particular, the present invention relates to a fluid composition for use in pressurized container, such as an aerosol.

BACKGROUND ART

The use of gas bags in the mining industry is well established. Typically, gas bags are used as plugs in drill or bore holes in order to provide support for the surrounding rock and reduce the likelihood of rock fall.

Conventional gas bags consist of a bag made from a resilient material (such as plastic) that is inflated by a gas produced during a chemical reaction that takes place in the bag, such as that of a mixture of an acid and a soda. However, these bags have the drawback of a high failure rate, for instance due to pre-inflation caused by a mixing of the reactants inside the bag during manufacture, storage, transportation and handling.

Some attempts have been made to overcome this problem. For instance, some attempts to use aerosols in gas bags have been made. The use of an aerosol reduces the likelihood of pre-inflation by keeping the reactants separate until such time as the aerosol is activated. However, aerosol propellants such as hydrocarbons result in an inflated gas bag being filled with a flammable gas.

Thus, there would be an advantage if it were possible to provide a fluid composition that allowed for the efficient and effective inflation of a gas bag, but which did not result in the gas bag being filled with a flammable fluid.

It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.

Throughout this specification, the term “comprising” and its grammatical equivalents shall be taken to have an inclusive meaning unless the context of use, indicates otherwise.

OBJECT OF THE INVENTION

It is an object of the present invention to provide a fluid composition which may overcome at least some of the abovementioned disadvantages, or provide a useful or commercial choice.

In a first aspect, the invention resides broadly in a fluid composition comprising a hydrocarbon gas or hydrocarbon gas blend, a carrier and an emulsifier.

Any suitable hydrocarbon gas or hydrocarbon gas blend may be used. For instance, the hydrocarbon gas may comprise butane or propane. In some embodiments of the invention, a blend of butane and propane (such as Liquid Petroleum Gas or LPG) may be used. A skilled addressee will understand that the relative proportions of butane and propane in the hydrocarbon gas blend are not critical and may vary as necessary.

The carrier may be of any suitable form. However, in a preferred embodiment of the invention, the carrier is suitable for the hydrocarbon gas or hydrocarbon blend to be dissolved or dispersed in the carrier. Thus, in a preferred embodiment of the invention, the carrier comprises water or a suitable dilute aqueous solution.

Any suitable type of emulsifier may be used in the fluid composition of the present invention. The precise nature of the emulsifier used in the fluid composition is not critical provided at the emulsifier assists in ensuring the fluid composition is a substantially homogeneous mixture. In some embodiments, the emulsifier may have surfactant properties. Alternatively, it is envisaged that, if required, a surfactant may also be added to the fluid composition. A skilled addressee will understand that any suitable surfactant may be used.

The fluid composition may comprise any suitable ratio of components. For instance, the hydrocarbon gas or hydrocarbon gas blend and carrier may together comprise up to about 99.9% of the fluid composition, while it is envisaged that the emulsifier may be present in quantities of up to about 10% of the fluid composition.

The ratio of hydrocarbon gas or hydrocarbon gas blend to carrier in the fluid composition is not critical and may vary depending on the type of hydrocarbon gas or hydrocarbon gas blend and carrier used in the fluid composition. However, it will be understood that the fluid composition must comprise a sufficient quantity of each component in order for the fluid composition to form a substantially homogeneous mixture.

In some embodiments of the present invention, the fluid composition may further comprise alcohol. Alcohol may be present in the fluid composition for a number of reasons, including reducing pressure in the container in which the fluid composition is stored and transported. Any suitable alcohol (or blend of alcohols) may be present. In a preferred embodiment of the invention, the alcohol may be ethanol.

In embodiments of the invention in which alcohol is present, the alcohol may assist in dissolving the hydrocarbon gas or hydrocarbon gas blend in the carrier. In addition, the presence of alcohol in the fluid composition may assist in the creation of a foam when the fluid composition is dispensed from a dispenser. Still further, the addition of alcohol may assist in reducing the flammability of the fluid composition.

When present, it is preferred that the alcohol comprises no more than about 10% of the fluid composition.

In some embodiments of, the invention, alternative substances to alcohol may be used. For instance, in one embodiment, acetone may be used instead of alcohol.

In a preferred embodiment of the invention, the fluid composition is substantially non-flammable.

In another aspect, the invention resides broadly in an aerosol dispenser containing a fluid composition comprising a hydrocarbon gas or hydrocarbon gas blend, a carrier and an emulsifier.

Any suitable hydrocarbon gas or hydrocarbon gas blend may be used. For instance, the hydrocarbon gas may comprise butane or propane. In some embodiments of the invention, a blend of butane and propane (such as Liquid Petroleum Gas or LPG) may be used. A skilled addressee will understand that the relative proportions of butane and propane in the hydrocarbon gas blend are not critical and may vary as necessary.

The carrier may be of any suitable form. However, in a preferred embodiment of the invention, the carrier is suitable for the hydrocarbon gas or hydrocarbon blend to be dissolved or dispersed in the carrier. Thus, in a preferred embodiment of the invention, the carrier comprises water or a suitable dilute aqueous solution.

In embodiments of the invention in which the carrier is a dilute aqueous solution, the dilute aqueous solution may contain any suitable material. For instance, the aqueous solution my contain one or more compounds or the like. For instance, in a preferred embodiment of the invention, the aqueous solution may one or more carbomers. Any suitable carbomer may be used. In a particular embodiment of the invention, the carbomer may include a cross-linked polyacrylic acid polymer such as Ultrez 10 manufactured by the Lubrizol Corporation.

The carbomer may be present in any suitable quantity in the aqueous solution. In some embodiments, the carbomer may be present in an amount of no more than 10%. More preferably, the carbomer may be present in an amount of no more than 5%. Still more preferably, the carbomer may be present in an amount of no more than 1%. In one particular embodiment, the carbomer is present in an amount of about 0.5% of the aqueous solution.

In some embodiments of the invention, the aqueous solution may include further compounds in addition to, or instead of, the carbomer. Such compounds may include coco betaine (such as that manufactured under the trade name Empigen BB) or coconut diethanolamide (such as that manufactured under the trade name Empilan FD). In some embodiments of the invention, the coco betaine or coconut diethanolamide is present in an amount of less than 50% of the aqueous solution. More preferably, the coco betaine or coconut diethanolamide is present in an amount of less than 25% of the aqueous solution. Most preferably, the coco betaine or coconut diethanolamide is present in an amount of about 10% of the aqueous solution.

In one embodiment, the aqueous solution may include about 0.5% carbomer and about 10% coconut diethanolamide. The advantages of this combination of components includes the production of a relatively long-lasting foam and a significant reduction in flammability. Specifically, the use of these components produces a slow burning fluid composition, but one which does not burn explosively.

It is envisaged that the use of these components will result in a fluid composition that requires mechanical agitation. For instance, the container or vessel in which the fluid composition is provided may require agitation (such as by shaking the container) after the container is gassed and/or prior to dispensing the contents of the container.

Although it has been stated that either coco betaine or coconut diethanolamide could be used in the fluid composition, it is preferred that coconut diethanolamide is used in preference to coco betaine. This is because it has been found that fluid compositions using coco betaine produce a relatively short-lasting foam and a fast burning (but not explosive) foam. On the other hand, the fluid composition using coco betaine does not require any mechanical agitation.

While some specific emulsifiers have been described above (carbomer, coconut diethanolamide and coco betaine), it is envisaged that any suitable type of emulsifier may be used in the fluid composition of the present invention. The precise nature of the emulsifier used in the fluid composition is not critical provided at the emulsifier assists in ensuring the fluid composition is a substantially homogeneous mixture. In some embodiments, the emulsifier may have surfactant properties. Alternatively, it is envisaged that, if required, a surfactant may also be added to the fluid composition. A skilled addressee will understand that any suitable surfactant may be used.

The fluid composition may comprise any suitable ratio of components. For instance, the hydrocarbon gas or hydrocarbon gas blend and carrier may together comprise up to about 99.9% of the fluid composition, while it is envisaged that the emulsifier may be present in quantities of up to about 25% of the fluid composition, and preferably up to about 10.5% of the fluid composition.

The ratio of hydrocarbon gas or hydrocarbon gas blend to carrier in the fluid composition is not critical and may vary depending on the type of hydrocarbon gas or hydrocarbon gas blend and carrier used in the fluid composition. However, it will be understood that the fluid composition must comprise a sufficient quantity of each component in order for the fluid composition to form a substantially homogeneous mixture.

In some embodiments of the present invention, the fluid composition may further comprise alcohol. Any suitable alcohol (or blend of alcohols) may be present. In a preferred embodiment of the invention, the alcohol may be ethanol.

In embodiments of the invention in which alcohol is present, the alcohol may assist in dissolving the hydrocarbon gas or hydrocarbon gas blend in the carrier. In addition, the presence of alcohol in the fluid composition may assist in the creation of a foam when the fluid composition is dispensed from a dispenser. Still further, the addition of alcohol may assist in reducing the flammability of the fluid composition, and may reduce the pressure of the fluid composition in the container in which it is stored and transported.

When present, it is preferred that the alcohol comprises no more than about 10% of the fluid composition.

In some embodiments, the aerosol dispenser may further comprise a propellant. Any suitable propellant may be used, such as, but not limited to, a hydrocarbon or combination of hydrocarbons, air, nitrogen or the like, or any combination thereof, or indeed any other propellant known to a person skilled in the art.

In other embodiments of the present invention, the propellant may be added to the fluid composition prior to the fluid composition being added to the aerosol dispenser.

In an alternative embodiment the difference in pressure between the interior of the aerosol dispenser and the ambient environment may be sufficient to propel the fluid composition out of the aerosol dispenser on actuation of the aerosol dispenser without requiring the addition of a propellant.

The fluid composition may be provided in any suitable aerosol dispenser. Preferably, the aerosol dispenser is adapted to house a pressurized fluid. Thus, the aerosol dispenser may be fabricated from metal, plastic or any suitable polymer blend or the like, or any combination thereof. In a preferred embodiment of the invention, the aerosol dispenser is an aerosol can.

Desirably, the ratio of the components in the fluid composition is such that, as the fluid composition is dispensed from the aerosol dispenser, the fluid composition forms a foam.

In yet another aspect, the invention resides broadly in a system for plugging a drill hole or bore hole, the system comprising:

-   -   an inflatable container, and     -   an aerosol dispenser located within the inflatable container and         containing an fluid composition comprising a hydrocarbon gas or         hydrocarbon gas blend, a carrier and an emulsifier,     -   wherein upon activation, the aerosol dispenser dispenses the         fluid composition to cause inflation of the inflatable         container.

Any suitable inflatable container may be used in the present invention. Preferably, however, the inflatable container is fabricated from a resilient, substantially leak-proof material. For instance, the inflatable container may be fabricated from plastic, such as, but not limited to HDPE.

In some embodiments of the present invention, the fluid composition may further comprise alcohol. Any suitable alcohol (or blend of alcohols) may be present. In a preferred embodiment of the invention, the alcohol may be ethanol.

In yet another aspect, the invention resides broadly in a method of plugging a drill hole or bole hole comprising the steps of:

-   -   a) providing an inflatable container including an aerosol         dispenser containing a fluid composition comprising a         hydrocarbon gas or hydrocarbon gas blend, a carrier and an         emulsifier;     -   b) at least partially inserting the inflatable container into a         drill hole or bore hole;     -   c) activating the aerosol dispenser to cause inflation of the         inflatable container.

In some embodiments of the present invention, the fluid composition may further comprise alcohol. Any suitable alcohol (or blend of alcohols) may be present. In a preferred embodiment of the invention, the alcohol may be ethanol.

A skilled addressee will understand that the present invention provides the advantage of reducing or eliminating the likelihood of pre-inflation of the inflatable container by separating the reactants in the manner discussed. In addition, on inflation, the resulting gas that inflates the inflatable container is substantially non-flammable, thereby reducing the likelihood of fire or explosion. It will be clearly understood that reducing the likelihood of fire or explosion in a mining environment (and especially in a coal mining environment) is a significant advantage.

Those skilled in the art will appreciate that the present invention may be susceptible to variations and modifications other than those specifically described. It will be understood that the present invention encompasses all such variations and modifications that fall within its spirit and scope.

In addition, those skilled in the art will understand that the percentages of each component in the fluid composition referred to herein could be weight % or volume %. 

1. A fluid composition comprising a hydrocarbon gas or hydrocarbon gas blend, a carrier and an emulsifier.
 2. A fluid composition according to claim 1 wherein the hydrocarbon gas or hydrocarbon gas blend comprises butane or propane, or a blend thereof.
 3. A fluid composition according to claim 1 or claim 2 wherein the carrier is suitable for the hydrocarbon gas or hydrocarbon gas blend to be dissolved therein.
 4. A fluid composition according to any one of the preceding claims wherein the carrier comprises water or a dilute aqueous solution.
 5. A fluid composition according to any one of the preceding claims wherein the hydrocarbon gas or hydrocarbon gas blend together comprise up to 99.9% of the fluid composition, and the emulsifier comprises up to 10% of the composition.
 6. A fluid composition according to any one of the preceding claims wherein the fluid composition further comprises an alcohol or blend of alcohols or acetone in amount of up to 10% of the fluid composition.
 7. A fluid composition according to any one of the preceding claims wherein the emulsifier comprises one or both of a carbomer or coconut diethanolamide.
 8. A fluid composition according to claim 7 wherein the carbomer and coconut diethanolamide together comprise about 10.5% of the fluid composition.
 9. An aerosol dispenser containing a fluid composition comprising a hydrocarbon gas or, hydrocarbon gas blend, a carrier and an emulsifier, the aerosol dispenser further containing a propellant.
 10. Mi aerosol dispenser according to claim 9 wherein the fluid composition is a fluid composition according to any one of claims 1 to
 8. 11. An aerosol dispenser according to claim 9 or claim 10 wherein the propellant comprises a hydrocarbon or blend of hydrocarbons, air, nitrogen, or a combination thereof.
 12. An aerosol dispenser according to any one of claims 9 to 11 wherein the aerosol dispenser is adapted to house a pressurized fluid.
 13. An aerosol dispenser according to any one of claims 9 to 12 wherein the ratio of components in the fluid composition is such that, as the fluid composition is dispensed from the aerosol dispenser, the fluid composition forms a foam.
 14. A system for plugging a drill hole or bore hole, the system comprising: an inflatable container, and an aerosol dispenser located within the inflatable container and containing a fluid composition comprising a hydrocarbon gas or hydrocarbon gas blend, a carrier and an emulsifier, wherein upon activation, the aerosol dispenser dispenses the fluid composition to cause inflation of the inflatable container.
 15. A system according to claim 14 wherein the inflatable container is fabricated from a resilient, substantially leak-proof material.
 16. A system according to claim 14 or claim 15 wherein the inflatable container is fabricated from HDPE.
 17. A system according to any one of claims 14 to 16 wherein the aerosol dispenser is the aerosol dispenser of any one of claims 9 to 13 and the fluid composition is the fluid composition of any one of claims 1 to
 8. 18. A method of plugging a drill hole or bole hole comprising the steps of: a) providing an inflatable container including an aerosol dispenser containing a fluid composition comprising a hydrocarbon gas or hydrocarbon gas blend, a carrier and an emulsifier; b) at least partially inserting the inflatable container into a drill hole or bore hole; c) activating the aerosol dispenser to cause inflation of the inflatable container.
 19. A method according to claim 18 wherein the inflatable container is fabricated from a resilient, substantially leak-proof material.
 20. A method according to claim 18 or claim 19 wherein the aerosol dispenser is the aerosol dispenser of any one of claims 9 to 13 and the fluid composition is the fluid composition of any one of claims 1 to
 8. 